SOLUTION: How do you solve: c-5d=2 2c+d=4

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Question 253809: How do you solve:
c-5d=2 2c+d=4
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!

c-5d=2
2c+d=4
double the first
2c-10d=4
2c+d=4
As you can see we have 2c in the first and 2c in the second
and after subtracting 10d we get 4
but we also get 4 after adding d
which means that d must equal -10d
d=-10d
which would lead to d being 0 or 1=-10
so d=0
therefore c=2